xcode 使用 UISearchBar 搜索表格视图

Searching a table view with UISearchBar

提问by user2014474

I am using this code to search through a UItableView:

我正在使用此代码来搜索 UItableView：

-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText {



if(searchText.length == 0)
{
    isFiltered = FALSE;
}
else
{
    isFiltered = TRUE;


    if (filteredTableData == nil)
       filteredTableData = [[NSMutableArray alloc] init];
    else 
        [filteredTableData removeAllObjects];

    for (NSString* string in self.itemArray)
    {
        NSRange nameRange = [string rangeOfString:searchBar.text options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch)];
        if(nameRange.location != NSNotFound)
        {
            [filteredTableData addObject:string];
        }
    }
}
[tableView reloadData]; 
[self.tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationFade];
}

Everything works fine, but if I press the cancel button which appears when I start editing, my list doesn't come back, but the search results remain. To show back the list, I have to begin typing, even a single character in the searchbar and then delete it or press the "x" to see all the list. Is there a way to block the cancel button? Or to show the list when it is pressed?

一切正常，但如果我按下开始编辑时出现的取消按钮，我的列表不会返回，但搜索结果仍然存在。为了显示列表，我必须开始输入，即使是搜索栏中的单个字符，然后将其删除或按“x”以查看所有列表。有没有办法阻止取消按钮？或者在按下时显示列表？

回答by Rahul Wakade

Implement - (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar delegate method of UISearchBar. In that add all objects(initial objects in table) in filteredTableData array and reload table.

实现 - (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar UISearchBar 的委托方法。在其中添加filteredTableData数组中的所有对象（表中的初始对象）并重新加载表。

   -(void)searchBarCancelButtonClicked:(UISearchBar *)searchBar
    {       
        [filteredTableData removeAllObjects];
        [filteredTableData addObjectsFromArray:self.itemArray];
        [tableView reloadData];
    }

Also you don't need to maintain flag isFiltered if you are using it for choosing data source array for reloading table(in table view data source methods). e.g.

如果您使用它来选择数据源数组以重新加载表（在表视图数据源方法中），则您也不需要维护标志 isFiltered。例如

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
   if(isFiltered) 
      return filteredTableData.count 
   else
      return self.itemArray.count
}

If you maintain data in filteredTableData array all time, you don't need to do this. Your method will look like-

如果您一直在filteredTableData 数组中维护数据，则无需执行此操作。你的方法看起来像-

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
      return filteredTableData.count 
}

Initially in init or viewDidLoad method of controller add all objects in filteredTableData and use only this array for reloading table.

最初在控制器的 init 或 viewDidLoad 方法中，添加filteredTableData 中的所有对象，并仅使用此数组来重新加载表。

Hence your method will look like-

因此你的方法看起来像 -

 -(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
 {
     if(searchText.length == 0)
     {
         [filteredTableData removeAllObjects];
         [filteredTableData addObjectsFromArray:self.itemArray];
     }
     else
     {
        [filteredTableData removeAllObjects];

        for (NSString* string in self.itemArray)
        {
            NSRange nameRange = [string rangeOfString:searchBar.text options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch)];
            if(nameRange.location != NSNotFound)
            {
                [filteredTableData addObject:string];
            }
        }
     }
     [tableView reloadData]; 
    }

回答by Bot

I don't use that method but use the following and it works perfectly

我不使用该方法，而是使用以下方法，它可以完美运行

- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name CONTAINS[cd] %@",searchString];
    self.filteredCustomers = [[self.customers filteredArrayUsingPredicate:predicate] mutableCopy];

    return YES;
}

- (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar
{
    [self.searchDisplayController setActive:NO animated:NO];
    self.filteredCustomers = nil;
    [self.tableView reloadData];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"CustomerCell";
    NSDictionary *customerObject;

    CustomerListCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (self.searchDisplayController.active) {
        customerObject = [[NSDictionary alloc] initWithDictionary:[self.filteredCustomers objectAtIndex:indexPath.row]];
    } else {
        customerObject = [[NSDictionary alloc] initWithDictionary:[[self.customerData objectAtIndex:indexPath.section] objectAtIndex:indexPath.row]];
    }
    cell.textLabel.text = [customerObject objectForKey:@"name"];
    cell.customerName = [customerObject objectForKey:@"name"];
    cell.customerId = [customerObject objectForKey:@"customer_id"];

    return cell;
}